Electrical oven and kiln.



L. H. e nnmes. ELECTRICAL OVEN AND KILN. APPLICATION FILED JUNE 29, 1911. RENEWED JULY 20, 1914.

1,1 30,392. Patented Mar. 2, 1915.

2 SHEETSSHEET 1 /.9 zz 20 .1? 2 24 Zdiinewaew v Inventor LWJon]fei2/&Q&idulg5 UNITED STATES nrENr enrich.-

LAWSON my cmmncs, n nnncrmcan ovnn speciilcation'orletteralatent.

Patented Mar. 2, 1915.

Application mm June 29, 1911, Serial no. access. fkenewec ,m 20.1914. mm so. new.

- .To all whomit may concern:

Be it known that I, LAWSON HENRY Gmnmes, a citizen of the United States, residing at Pasadena, in the county of Los :Angeles and State of California, have invented a new and useful Electrical Oven and Kiln, of which the following is a specification. .This invention relates to an apparatus adapted for use use bakers oven or as egottery', brick, malt or other kiln, or for ing'or drying'substanees requiring such operation; and also as a tempering and. annealin oven or kiln for metal working.

@119 invention may be constructed elther in circular or angular plan, the circular form being preferred for'strength and to guard against.- liability of damage. irom expension and contraction. v

The aecompanving drawingsilhistrate the invention.

Figure 1 is a front elevation of a circular kiln'constructed in accordance with this invention. Fig. 2 is a vertical section oi the kiln shown in Fig. 1. Fig. 3 is a view partly in section on line m, Fig. 2. Fig. 4; is a plan section. on line w Figs. 1 and2. Fig. 5 is a. frontelevation of a rectangular 111111 or .oven constructed in accordance with this invention. Fig. 6 is a sectional elevation of the kiln shown in Fig. 5, from line w Figs.

5 -;7,.. 8 and 9. -Fig. 7 isa sectional elevation i rom line 'w,'Fig. 6'. Fig. 8 is a'plan section -on'linem Figs. 5,6 and 7. Fig. 9 isa plan 'tS GZtlQII on line a", Figs; 5, (tand- 7.'. Fig. 10 is a reduced sectional elevation from; line 92 9, Figs.'5,'6, 8 and 9.

The kilnor oven is provided'with chambers arranged beside each other and com munic'atingwith each other at -two levels and constituting the resistance chamber having :an'air inlet at its lower part, and the oven chamber having a draft outlet at the lower portion discharge of heated air, steam or gas. Preferably the two chambers cemimunicate with each other at top and bottom.

" Referring now to the circular form shown in Figs. 1, 2,3 and 4, the foundation 1 supports the external heat insulating wall 2 and l 1 there is a heat-insulating wall 25 and aheatthe refractory heat-transmitting wall 3,.both of which are'circular in plan section and are spaced "apart toform between and within them the resistance chamber 4 and the oven chamber 5, which are beside each otherso that heat from the resistance chamberwill heat insulatingtop 6 and the heat transmitting walls 3 supportthe permeable oventop 7 which is spaced apart from the heat-insulatmg to 6 ;to form an air chamber 8 overlying t eo'ventopf and communicating wlth the ports 9'in said even top, so that the chambers 4 and 5 communicate at their tops throu h the air passage 8 and perforations 9. 'I echambers 4 and 5 communicate at their bottoms: through ports'10. Ports 11 open from the external air through the heat insulatm walls 2 into the resistance chamber-4. T e ports 10 and 11 are arranged in .ahned pairs and both portsof any air may be Whollyclosed or wholly opened, or the men one. may be partly or wholly opened whflethe enter one is closed- The closures for this purpose may be any iorm of damper as the burnt fire-01a plugs 12 having handies 13, and adapts tobe inserted into and withdrawn from said ports 'to control the flow of air within the judgment of the operator. Bridges 14 formed -b bricks proeeting irom either of the wafis 2 or 3 extend across the resistance chamber in checker-work form to support the resistance 15- which may be calorite rods laid on the bridges but may be calorite cast-iron,'German silver or any other suitable resistance material capable of standin high heat. A 'draft outlet 16 which may centrally arranged as shown in F igs. 2 and-4 communicates. with: the external air through a flue l7 extending under a portion of the flooranrl opening into the stack 18. The resistance rods 15 are connected in series by connectors 19- and with opposite polesof-an electrical supply not shown through the connectors 20 and. 21 and switch 22'. In the form shown connection for direct current is illustrated. Alternating current ot-any suitable phase may .be used. by employ' suitable connections well-known in theigictrieal engineering art. A door-way 23 isprovided and may be closed by any suitable means asby brick- ;work 24 shown in Fig. 1.

In the'form shown in Figs. 5, 6, 7,,8 and 9,

that it is straight instead! dfemuii The are lit

the sameis-prefided wah a. vertically sliding door 30 counter-balanced by the pulley 1 supportedline 31 and weight 32 in a com- In other respects than heretofore p t. noted t 'efconstruction of the rectangular oven is practically the, same as that described for-the circularoven, and many of the ele- 15 ments in Figs. 5 to inclusive, that correspond to arts shown in Figs. 1, 2, 3, 4 are indices. v

The ports 9 and 9" will be located at such points as may, in the judgment of the constructor, be preferable for the particular work in view. Sometimes itmay be advisable to introduce the air in greater volumeon one side than the other, of'the oven; 5 or near' the periphery or only at the center;

in each of which cases the ports will be located as desired. No illustration is attempted of. all the different arrangement of ports that may be employed. The stack may 'or may not be provided with a damper in the usual 'manner. No such damper is shown in the drawings as it is preferred to control the draft by'means of the plugs 12 which may be pushed in so as to open the outer 85 and close the inner of its alined ports,.thus admitting air to the resistance chamber 4 only; or may be drawn out by the handle 13 -so as to close both portslO and 11-; ormay be drawn out only sufliciently far to open 40 the inner port- 10 and leave the outer port 11 closed; or maybe entirely removed thus allowinggboth alined ports to be open.-

In practical use the substance to be heated or baked will be placed inside the heating t5 chamber 5 and the door way will be closed and the current turned onto the resistance.

The outside ports 11 will be closed so that no external air is admitted, and the inner ports 10 will be open so that air may circulate freely from and through the chambers and inner gorts. The hot air will be re' tained in t e retort by the gravity of the colder air in the flue 17 and stack 18; but any pressure from steam or gases formed,

56 and from expanded air is relieved by the opening 16, flue 17 and stack 18. The further operation of the furnace can be directed and controlled by the attendant in accordance with his judgment depending 60 upon the'use for which oven or kiln is em loyed.

hecolumn, of air in the stack and the air in theflue under the floor of the irmer oven chamber serves as a yielding seal for the ct outlet 16 that is below the-levels of the ports I shown in Figs. 5, 6-,

mdicated y corresponding characters with which communicate between the chambers; and such s'eal will be maintained automatically during all the heating, oxidizing, baking and burning operations. The material known as" calorlte is the common general electric resistance composed of nickel and chromium. V

I claim 1 1. A kiln or oven comprising outer and lIlIlU. chambers,*ports between the chambers at top and bottom thereof, an air-chamber overlying the top of the inner chamber and commumcating with the top ports, electrical resistance in one of the chambers, a stack, an outlet in the floor of the other chamber, and

a flue connecting between the outlet and the stack. I

2. A kiln or oven comprising two chambers communicating with each other at two levels, resistance in one of the chambers; there bein an outlet from the other chamber below 7th of said levels, and means to yieldingly seal he outlet.

3. A kiln or oven comprising two chambers communicating with each other at two levels, electrical resistance in one of the chambers; there being inlets for external air into such chamber; means to close said inlets, there being an outlet from the other chamber below both of said levels, and means to yieldingly seal said outlet.

4. A kiln or oven comprising two chambers communicating with each other at two levels, electrical resistance in one of the chambers; there being an outlet from the other chamber, and alined ports in the walls of the two chambers; plugs slidable in said ports to control the same, and means to i Q yieldingly seal the outlet.

5. A kiln or oven comprising an outer wall; an inner wall; there being a chamber between said walls; bridges in said chamber; electrical resistance on the bridges; there being ports at top and bottom of the inner wall and an outlet from the. inner chamber below the levels of said ports; and means to yieldingly seal the outlet.

6. A kiln or oven comprising an outer wall; an inner wall; there being a chamber between said walls; bridges in staggered relation with each other in said chamber; electrical resistance on the bridges; there being ports at top and bottom of the inner wall, and an outlet from the inner chamber below the levels of 7 said ports; and means to yieldingly seal the outlet.

7. A kiln or oven comprising an outer wall; an inner wall; there being a chamber between said walls; bridges in said cham ber; electrical resistance on the bridges;

there being ports at top and bottom of the 8. A kiln or oven comprising an outer wall; an inner wall; there being a chamber between said walls; bridges in said chamber; electrical resistance on the bridges; there being ports at top and bottom of the inner wall, and an outlet from the inner chamber below the levels of said ports; a flue leading from the outlet; a stack communicating with the flue; there being ports in the outer wall, and means to close said ports.

9. A kiln or oven comprising an outer wall; an inner wall; there being a chamber between said walls; bridges in said chamber; electrical resistance on the bridges; there bein ports at top and bottom'of the inner wal, and an outlet from the inner chamber below the levels of said ports; a flue leading from the outlet; a stack communicating with the flue; there being alined ports in the outer and inner 'walls; and plugs slidable in said ports to open and close the same.

10. A kiln or oven comprising two walls forming chambers communicating with each other at two levels, bridges formed between the walls, and electrical resistance on the bridges.

11.. A kiln or oven comprising two chambers communicating with each other at two levels, and electrical resistance in one of the chambers and substantially encircling v 

